Nonslip spindle for phonograph turntables



Aug. 18, 1942. F. J. OFFEN NONSLIP SPINDLE FOR PHONOGRAPH TURNTABLES Filed May 13, 1941 rnemea A... is, 1942 NONSLIP SPINDLE TUB FOR PHONOGRAPH NTABLES Francis John Often, Swindon, England, assignor to The Garrard Engineering 3; Manufacturing Company, Limited, Swindon, Wiltshire, England, a corporation of Great Britain Application May 13, 1941, Serial No. 393,165

6 Claims. (Cl. 274-10) This invention relates to means for preventing slipping or skidding of records arranged onthe turntable of a phonograph, and more particu larly to a spindle provided with novel means for gripping and locking the records so arranged on the turntable. V The non-slip spindle of the invention is particularly adapted for use in connection with an automatic phonograph of the type where a stack of records'is supported above the turntable, and the lowermost record of the stack is selectively dropped upon the turntable. The general arrangement and operation of a phonograph of this above type is shown in the co-pending United States application of Francis'John Oiien,

for improvements in Automatic stop mechanism for magazine phonographs, Serial No. 383,018, assigned to the same assignee as is this case.

It had been recognized in the art that when several records are arranged one on the other on a turntable, the uppermost record may. slip, causing it to lag behind and creating va disagreeable tone distortion. Such slipping or skidding of the records is due to the low friction between the comparatively smooth record surfaces.

In accordance with the invention I provide a stationary centering spindle having a sleeve rotatably mounted thereon. The rotatable sleeve is provided with a plurality of outwardly curved leaf springs for engagement with the edge of the Center hole of the records. In a preferred embodiment of the invention, the leaf springs on the rotatable spindle are provided with humps or slopes extending in different vertical planes. Thus, each of the leaf springs engages and interlocks with at least one of the stacked records, ensuring uniform rotational speed of the records on the turntable.

It is accordingly an object of the present invention to provide a novel gripping and locking means for records arranged one onthe other on a phonograph turntable.

Another object of the invention is to .provide a phonograph with a stationary centering spindle and a rotatable sleeve thereon, the sleeve being provided with a plurality of outwardly projecting leaf springs to grip a number of records.

- Still another object of the invention is to provide a centering spindle for phonographs of the type referred to, having a plurality of leaf springs on a rotatable sleeve, said leaf springs having slopes or humps arranged in different vertical planes.

These and further objects of the invention will become more apparent in the following description of a preferred embodiment of the invention illustrated in the drawing, wherein:

Figure 1 is a view in perspective of a phonograph embodying the non-slip spindle of the invention. v e

Figure 2 is a broken away front view of the spindle, illustrating the rotatable sleeve having several leaf springs.

Figure 3 is a rear view corresponding to Fig- 111'8 Figure 4 is a section taken on the line 44 of Figure 2;

Figure 5 is a section taken on the line 55 of Figure 2. a

Referring to the drawing, the record changer phonograph comprises base p ate ill. turntab e ll rotatably mounted above base plate Ill, and

stationary centering spindle l2. Spindle l2 has Stationary centering spindle l2 has a reduced portion 22 on which a sleeve 23 is mounted in. a freely rotatablerelation. Sleeve 23 is provided with four leaf springs 24, 25, 26, 21. As seen in Figure 4, springs 24 and 28- have sure stantially the same shape. Springs 24 and 28 each have an upper hump or slope 30 and a lower one 3!. Sleeve 23 embodies a ring-shaped recess 32 about its central portion wherein springs 24 and 28 are rigidly secured. The upper and lower ends of springs 24 and 28 can thus slide within longitudinal recesses 34 and 3B in spindle 23. Springs 25 and 21 are mounted in longitudinal recesses 35 and 31 of spindle 23.

As clearly shown in Figures 3 and 5, spring 21 has a hump 40 arranged above ring shaped recess 32. Spring 21 is secured in ring-shaped recess 4! arranged in the lower part of spindle 23. Spring 25 shown in Figures? and 5 has a hump 42 arranged in a different vertical plane from the one passing through hump 40 of spring Spring "is also secured in ring portion 4|. The upper free ends of springs 25 and 21 are thus free to slide in longitudinal recesses 35 and 31.

Due to the action of pusher plate 21, the low- I A pusher plate, is provided above base ermost record R supported on shoulder i3 spindle I2 is pushed down the spindle l2 onto' the turntable ii. The central hole of the pushed record then engages with sleeve 23 and its springs. The record presses against the various humps on the four leaf springs 24, 25, 28, 21. When the turntable is rotated, all the records thereon are rotated with the same rotational speed because their central holes are interlocked by the bumps on the plurality leaf springs 24, 25, 26, 21 with varying positioned and sloped humps. The lowermost humps 3| on leaf springs 24 and 26 engage with the record directly above the turntable to cause spindle 23 to rotate with the same speed as the turntable. The other humps serve to interlock with the center holes of records arranged in various vertical planes, and hence it will be seen that the uniform speed of the records is ensured and skidding thereof is prevented.

Various changes and modifications may be made to the details of construction of the invention without departing from the broader spirit and scope thereof, as set forth in the following Claims.

I claim:

1. In a phonograph for playing disk records, the combination with a rotatably mounted turntable, of a stationary centering spindle for extending through the central openings of the record, a sleeve rotatably mounted on said spindle, and a plurality of outwardly projecting springs on said sleeve for gripping and locking the inner edge of the central openings of the records.

2. In a phonograph for playing disk records, the combination with a rotatably mounted turntable, of a stationary centering spindle, a sleeve rotatably mounted on said spindle and projecting above said turntable, and a plurality of curved springs on said sleeve ior engagement with the central opening of a record for looking it in playing position on the turntable.

3. A stationary centering spindle for engaging and interlocking the central opening or disk records comprising a sleeve rotatably mounted on said spindle, a plurality oi leaf springs on said spindle, each of said springs having at least one hump projecting radially from said sleeve.

4. A stationary centering spindle for engaging and interlocking the central openings of disk records including a sleeve rotatably mounted on said spindle, a plurality of leaf springs longitudinally arranged on said spindle, said springs having humps in different vertical planes for engagement with the central opening of different superimposed disk records.

5. A stationary centering spindle for engaging and interlocking central openings of disk records, comprising an upper portion bent with respect to the lower portion thereof, a shoulder on said upper spindle portion for supporting a stack of records thereon, a sleeve rotatably mounted on said lower spindle portion, and a plurality of outwardly curved springs on said sleeve for engagement with the central openings of the records.

6. A stationary centering spindle for engaging and interlocking the central openings of disk records comprising a sleeve rotatably mounted on said spindle, a plurality of longitudinal recesses in said sleeve, a leaf spring in each of said recesses arranged parallel with the spindle, said leaf springs having at least one hump respectively arranged in different vertical levels, each of said leaf springs being secured in its recess in a manner wherein at least one end thereof is freely slidable in the recess.

FRANCIS JOHN OFFEN. 

